Every once in a while, you read a book that changes you -- inspiring your career, clarifying your goals, challenging your thinking. The right book can give you the courage to start your business, the reality check that you're not yet ready or the quiet affirmation that you're not alone in your fears or ambitions. It can set you on your path to success.

We asked our expert contributors to name the one book that most influenced and inspired their careers. Their responses ran the gamut from fiction to history to business to self-help books.

Here's a sampling of 15 of our experts on the books that most inspired them and why.

Jason Womack: 'Atlas Shrugged' by Ayn Rand

"To start a business, you just need to define a problem. But to wake up every day, no matter what, and DO that business, you need a reason. Ms. Rand taught me that focusing on a purpose is the best way to make a difference to my world." -- Jason Womack

Jim Joseph: 'Ogilvy on Advertising' by David Ogilvy

"I read [this book] when I was in college, studying marketing. It helped me to cement that this was the field for me and that at the end of the day, it's all about creativity. Although at the time it refered to advertising, it's actually applicable to all parts of the marketing mix. Ogilvy gives rules, but then breaks them. I love it!" -- Jim Joseph

Mark J. Kohler: 'Richest Man in Babylon' by George Clason

"This was one of the first business books I read and it taught me that ‘saving’ money is equally as important as ‘making’ money. I’m now requiring my teenage children to read the book and report back to me on how it impacted them." -- Mark Kohler

"This book was seminal for me early in my business career. It brought structure and insight to the at-the-time mysterious subject of leadership, and it addressed matters of both the head and heart." -- Mark Sanborn

Jay Turo: 'The Strategy Paradox' by Michael Raynor

"This book has had great influence on me. The author's key point is that businesses are usually managed much too conservatively and, while counter-intuitive, the best strategy is often the riskiest one." -- Jay Turo

"These two books from Alfred Chandler should be on the must-read list for anyone interested in the history of the modern corporation.

The Visible Hand describes how the modern form of the corporation emerged in the U.S. in the mid 19th century -- railroads, steel and oil companies grew large enough that ownership no longer equaled hands-on management. Professional managers were hired to run companies and functional departments -- sales, manufacturing, finance, etc. -- emerged.

Strategy and Structure describes how a new form of corporate organization emerged in the 1920's -- divisionalization -- in response to multiple product lines and large geographic distances in the U.S. First practiced by Dupont, then adopted by General Motors, Sears and Standard Oil, companies with multiple operating divisions became the norm in the decades that followed."
-- Steve Blank

Punit Arora: 'Blue Ocean Strategy' by W. Chan Kim and Renee Mauborgne

"This book develops the concept of and shows how to use 'blue ocean strategy.' It highlights, for example, how to make the competition irrelevant by creating a new market space or a blue ocean rather than focusing on out-performing the competition in the existing industry. The book has spun-off whole new industries and markets including that of strategy consultants." -- Punit Arora

Shari Alexander: 'The 4-Hour Workweek' by Tim Ferriss

"This book helped me in two very distinct ways. First, it opened my eyes to how business can be sourced and conducted globally for even the smallest of businesses -- the global economy isn't limited to the big corporations anymore. Second, it was life changing because it made me, as an entrepreneur, ask deeper questions about what I want out of life, not just the business."
-- Shari Alexander

Ross Kimbarovsky: 'Tribal Leadership' by Dave Logan, John King and Halee Fischer-Wright

Tribal Leadership, by Dave Logan, John King and Halee Fischer-Wright(HarperBusiness, 2011)

"Despite conventional wisdom, research reveals that naturally forming small groups of people within organizations, and not leaders, drive success, quality and innovation. This book provides a great framework for companies to build a culture of success, quality and innovation."
-- Ross Kimbarovsky

David Koji: 'Switch: How to Change Things When Change Is Hard' by Chip Heath and Dan Heath

Tom Cochran: 'Victorian Internet' by Tom Standage

"This is a fascinating history of the telegraph and how it was arguably more impactful on communications than the Internet. Standage articulates the parallels between the two paradigm shifts very well and illustrates how even large-scale technology innovations have similar socio-political repercussions through the centuries." -- Tom Cochran

Chris Kocek: 'Zag: The Number One Strategy of High Performance Brands' by Mary Neumeier

"Most books end up saying the same thing 100 different ways. This book has no fluff and gets straight to the point on every page. The pictures do the talking. The prose fills in the gaps. If more business books were written like this, the world would be a better place." -- Chris Kocek

Ryan Himmel: 'The Art of War' by Sun Tzu

"I especially find this book to be helpful for businesses that are in the early stages of development as it teaches them to prepare for the many types of situations they may experience. As we all know, one of the biggest obstacles to overcome as an early-stage company is managing the element of the unknown. Strategy and preparation can, in many ways, guide a company and help mitigate future mistakes." -- Ryan Himmel

Your favorite books

We asked readers to tweet and send us the names of the books that most influenced and inspired them. We got hundreds of replies. Here are some top choices: